The present invention is directed to a processing apparatus of the type which includes upper and lower tanks for holding a processing fluid and a narrow processing chamber located between the tanks through which a sheet of photosensitive material is advanced for processing of latent images on the photosensitive material. Processing fluid is delivered to opposite sides of the photosensitive material from each of the tanks through an elongated discharge opening for forming a fluid layer on each side of the photosensitive material. A return drain is provided on each side of the photosensitive material for removing and returning the processing fluid to the sump tank. Example of such devices are illustrated in U.S. Pat. No. 4,989,028; U.S. Pat. No. 4,994,840; and U.S. Pat. No. 5,059,997. Such devices are often referred to as fluid suspension processors.
In order to obtain high velocity fluid streams from the discharge openings on to the photosensitive material, it is necessary to provide a thin uniform discharge opening. Prior art devices have had to employ costly manufacturing materials and techniques in order to obtain uniform fluid streams. Typically, prior art devices have had to use rigid metal parts in order to obtain the uniform fluid streams which not only add to the cost of the device but also add significantly to the weight of the device thus making it more difficult to service and repair. Prior art devices have also been difficult to assemble and disassemble. The fluid forces acting on the parts also make it more difficult to maintain uniform fluid streams. The thermo cycling experienced by the device further adds to the difficultly in maintaining uniform spacing of the discharge opening. During the course of a typical day, the device will go through various standby cycles in addition to being turned on and off at least once which causes significant temperature increases and decreases to occur in the device. This repeated thermo cycling makes it difficult to maintain a uniform spacing in the parts that form the fluid stream over an extended period of time. The effects of thermo cycling are even more difficult to resolve when plastic materials are employed to make the parts that form the discharge openings.
The present invention is directed to a fluid suspension processor which provides uniform thin discharge of processing fluid which can be easily manufactured, assembled or disassembled, and can be made of non rigid plastic material thereby permitting the utilization of low cost materials and manufacturing techniques.